Method, apparatus and system for fiberizing molten mineral material

ABSTRACT

A method for converting molten material into filamentous form of fibers consisting of discharging the molten material to at least one spinner assembly disposed in the region of a pickup chamber, circulating a conveying medium through a duct work system including a pickup chamber in the region of the spinner assembly and controlling the temperature and velocity of the conveying medium in a manner to produce fibers having a minimum shot content and good strength and resiliency characteristics, an apparatus and system for converting molten material into filamentous form of fibers including a cupola for the molten material having a discharge spout, a duct work system, means for circulating the conveying medium through the duct work system, at least one pair of spinner assemblies in the region of a pickup chamber in the duct work system, feed means for directing the molten material to each of the spinner assemblies and means for maintaining the quantity discharged to each spinner assembly substantially uniform.

United States Patent [1 1 Eriksen 51 Jan. 9, 1973 Herlui N. Eriksen,Drive, Burlington, NJ.

[22] Filed: Sept. 10, 1970 [21] Appl. No.: 71,148

[76] Inventor: 22 Laclede [56] References Cited UNITED STATES PATENTS1,837,836 12/1931 Powell "65/10 3,615,009 10/1971 Norton ..65/10XFOREIGN PATENTS OR APPLICATIONS 780,742 11/1955 GreatBritain ..65/l0165,884 10/1949 Austria ..65/10 Primary Examiner-Robert L. Lindsay, Jr.Attorney-Howson and Howson [57] ABSTRACT A method for converting moltenmaterial into filamentous form of fibers consisting of discharging themolten material to at least one spinner assembly disposed in the regionof a pickup chamber, circulating a conveying medium through a duct worksystem including a pickup chamber in the region of the spinner assemblyand controlling the temperature and velocity of the conveying medium ina manner to produce fibers having a minimum shot content and goodstrength and resiliency characteristics, an apparatus and system forconverting molten material into filamentous form of fibers including acupola for the molten material having a discharge spout, a duct worksystem, means for circulating the conveying medium through the duct worksystem, at least one pair of spinner assemblies in the region of apickup chamber in the duct work system, feed means for directing themolten material to each of the spinner assemblies and means formaintaining the quantity discharged to each spinner assemblysubstantially uniform.

10 Claims, 15 Drawing Figures PAIENTEDJM 9 I973 SHEET 20F a FIGZ.

. INVENTOR'. BY HERLUF N. EFHKSEN WWW ATTYS PATENTEDJAN 9 I975 3.709,670

sum 3 OF 6 HERLUF N. ERIKSEN INVENTORZI PATENTEDJAN 9197a 3.709.670

sum [1F 6 INVENTORI HERLUF N. ERIKSEN BY WW ATT YS.

PATENTEUJAN 9191a 3.709.670

sum 5 or 6 INVENTOR: HERLUF N. ERIKSEN PATENTEDJAN 9197a SHEET 6 BF 6ATTYS.

METHOD, APPARATUS AND SYSTEM FOR FIBERIZING MOLTEN MINERAL MATERIAL Thepresent invention relates to improved system and apparatus forfiberizing bulk material.

The invention is directed to an improved system and apparatus forconverting molten material, such as slag, glass or fusible rock intofilamentous form of fibers such as are generally known as slag wool,glass wool, or mineral wool and the like.

There are many known processes presently used for this purposeincluding, for example, the process wherein a powerful blast of gas,usually air, is directed against the molten slag to fiberize the same.In other instances, the molten slag is directed onto the periphery of aplurality of spinner heads which are rotating at rapid speed, again tocause the desired fiberization of the peripherally discharged droplets.

Even though these processes are generally satisfactory, they are not aseffective in producing fibers having a comparatively low shot contentand also the desired characteristics such as good strength andresiliency. The shot is formed during the fiberization and is usually inthe form of a small globule formed on the end of the fiber which, insome instances, is discharged from the fiber during processing. Forexample, in the production of wet felt, a high shot content can jam thescreen in the forming machines thereby resulting in down time for repairand replacement. Additionally, it has been found that board producedfrom fibers having a high shot content are non-uniform in cross section,presenting handling problems, and also resulting in damage to the boardswhen they are in face-to-back relation.

With the foregoing in mind, an object of the present invention is toprovide an improved system and apparatus for converting molten vitreousmaterial into fibers which is of comparatively simplified constructionand incorporates novel features whereby the shot content is maintainedat a minimum and the fibers produced are of a superior quality. To thisend, the system includes a pair of spinner assemblies which receive themolten vitreous material from a discharge spout of a cupola and fiberizethe molten material in a pickup chamber where the velocity andtemperature of the conveying medium, air, is controlled in such a mannerto produce fibers having a minimum shot content and good strength andresiliency characteristics. Another important feature of the presentinvention in producing fibers of this type is the feed arrangement forthe spinner heads which broadly includes a tiltable trough communicatingwith the discharge spout of the cupola which is arranged to supplysubstantially equal quantities of the molten vitreous material to eachof the spinner head assemblies. The spinner heads of each assembly aremotor driven and, in accordance with the present invention, load sensingmeans is provided for sensing load of the motors for each assembly andselectively and automatically regulating the feed flow to each spinnerhead assembly when the load on one exceeds the other.

These and other objects of the present invention and the variousfeatures and details of the operation and construction of the system andapparatus of the present invention are hereinafter more fully set forthwith reference to the accompanying drawings.

FIG. 1 is a view showing the system and apparatus for manufacturingmineral wool incorporating the present invention;

FIG. 2 is a view taken along lines 2-2 of FIG. 1 showing the dischargeend of the cupola and the spinner assembly;

FIG. 3 is a fragmentary side elevation view showing the pickup chamberand the details of the system for controlling discharge of the moltenmaterial to the spinner assembly;

FIGS. 4 and 5 are enlarged sectional views taken on lines 4-4 and 5-5respectively of FIG. 3;

FIG. 6 is an enlarged sectional view taken through the pickup chamberand spinner assembly showing the flow of conducting air through thepickup chamber;

FIG. 7 is a side view partly in section showing a portion of the pickupduct and return air duct;

FIG. 8 is a fragmentary view of the tilt control mechanism for the slagdischarge trough;

FIGS. 9, 10 and 11 are enlarged sectional views taken on lines 9--9,l0l0 and 1l-ll respectively of FIG. 8;

FIG. 12 is an enlarged sectional view of the tilting discharge troughtaken on lines 1212 OF FIG. 11;

FIG. 13 is a view showing extreme tilt positions of the dischargetrough; and

FIG. 14 is an electrical schematic of the control system for the tiltingdischarge trough assembly;

FIG. 15 is a sectional view taken on lines 15-15 of FIG. 3.

Considering now the principal elements and broad details of the systemof the present invention and with particular reference to FIG. 1 of thedrawings, a system and apparatus for making fibers from a fiberizablemolten material in accordance with the present invention includes meanssuch as a conveyor 10 for delivering the fiberizable material to thecharging sleeve 12 of a cupola 14. The cupola is of conventionalconstruction and includes a charging valve 16 whereby the cupola may befilled to a predetermined level, and a discharge spout 18 at its lowerend. Conventional heating means in the form of a series of gas nozzles20 and a bustle pipe 22 circumscribe the lower end of the cupola toprovide means for selectively controlling the temperature of thefiberizable material at the discharge end of the cupola.

The molten material discharged from the cupola is directed to a pair ofspinner assemblies 32 which cause fiberization thereof. The spinnerassembly heads are disposed in the region of a pickup chamber 40, whichis at the juncture of an upwardly extending pickup duct 42 through whichthe fibers are conveyed in a stream of air, and a return air duct 44.Means, described in more detail hereinafter, is provided for controllingthe temperature and velocity of the conveying medium through the pickupchamber 40 to facilitate production of fibers having a desired smallshot content and superior characteristics.

The pickup duct 42 discharges into a separator 46 which separates thefibers from the entrainment air. The entrainment air is then passedthrough a blower 48 whereupon part of the entrainment air is directed toa wet scrubber 50 through duct work 52 and part is directed to therecirculating or air return duct 44.

The fibers from the separator pass through a rotary discharge gate 60 toa granulator 62 and rotary screen 64. In the rotary screen 64 the finershot and foreign particles are separated from the fibers and the fibersare discharged at the end of the screen to a weighting hopper 66 forbailing in a conventional bailer 68.

There is shown in FIG. 1 a conventional system for supplying the heatedgases for the bustle pipe 22 and gas nozzles 20. This system includes astack 71 communicating with outside air, a blower 73 and a preheater 75.There is also a discharge stack 77 which may discharge directly from thecupola to the atmosphere. There is also provided a duct work 79communicating with the discharge stack 77 which vents into a venturiscrubber 81, the discharge air being withdrawn through the scrubber by ablower 83 to a secondary discharge stack 85.

Considering now the specific details and arrangement of the system andapparatus and with reference to FIGS. 8 and 9, the molten materialdischarged from the discharge spout 18 of the cupola is directed to atilt trough 91, the outer terminal ends of which overlie a pair of feedtroughs 93 and 95 which direct the molten material to a pair of spinnerassemblies 32. Each of these spinner assemblies comprise four spinnerwheels 95a, 97a, 99a and 101a. The other group of spinner wheels aredesignated by the same numeral with a b subscript. In each group, pairsof the spinner wheels are actuated from a motor source through suitabletransmission means. Thus, the spinner wheels 95a and 970 are driven bymotor M through transmission T wheels 99a and 101a are driven throughmotor M and transmission T Motors M and M drive the wheels 95b, 97b and99b, 101b through transmissions T and T An important feature of thepresent invention for controlling the shot content and thecharacteristics of the fibers is the provision of means for maintainingsubstantially equal flow of molten material to each of the spinnerassemblies. To this end, the tilt trough 91 is pivotally mounted on anaxis 107 and a linkage system broadly designated 109 connects the tilttrough to a motor actuator M More specifically, the linkage systemincludes a triangular pivot arm 111 pivotally mounted on the troughsupport brace 113, a first tilt rod 115 connecting a lever arm 1 17mounted on the tilt trough to the pivot arm 111 and a second tilt rod121 connecting the pivot arm 1 l l to themotor M Referring now to FIG.14 by way of example of one type of electrical circuitry which may beutilized to adjust automatically the angle of the discharge trough so asto maintain the loading on the two sets of spinner heads substantiallyequal, motor bank M represents the one or more parallel-connected motorswhich drive one set of spinner heads, and motor bank M, represents theone or more parallel-connected motors which drive the other set ofspinner heads; for example, motor bank M may comprise motors M, and Mparallel to each other, and motor bank M may comprise motors M and Mconnected in parallel with each other. Alternating line current source100, which may be the usual 115 volt AC line, is connected across themotor banks M and M in parallel, and typically a switch 102, which maybe manually or automatically operable, is connected in series with onelead from the power source to permit turning on and off of the two motorbanks. A pair of variably-tapped resistors 104 and 106 are supplied withcurrents proportional to the currents operating motor banks M, and M,respectively, by means of respective current-sensing transformers 108and 110. The latter transformers may each comprise a conventionalso-called doughnut" transformer, or a simple single turn of wire aroundthe lead to the corresponding motor bank. The polarity of theconnections and of the transformer couplings is such that the upperterminal 111 of resistor 104 and the lower terminal 112 of resistor 106are at any instant of time of the same polarity with respect to theopposite ends of the resistors, which are directly interconnected bymeans of the lead 114. The variable taps 112 and 114 of resistors 104and 106 are connected respectively through rectifiers 118 and 120 toseparate input terminals 122 and 124 of the proportioning relay circuit126.

Referring now to the operation of the portion of the circuit thus fardescribed, when switch 102 is closed, alternating current from source100 flows through both of the motor banks M and M to operate thecorresponding spinner heads, The currents in the leads and 132,supplying motor banks M and M, respectively, increase as the load on thecorresponding motor bank increases and, in general, these two will besubstantially equal when the loads are equal. Accordingly, when thedelivery of molten material to the two sets of spinner heads issubstantially equal, the loads on the corresponding motor banks areequal as are the currents in leads 130 and 132. Under these conditionsthe voltage at the top terminal 111 of resistor 104 will be equal to thevoltage at the lower terminal 112 of resistor 106 with respect to theirmutual connecting line 114, and accordingly, with taps 112a and 114asimilarly positioned, there will be no difference in voltage between thecathode elements of the rectifiers 118 and 120. The latter rectifiersserve to rectify the applied alternating current and to produce, atterminals 122 and 124 uni-directional negative voltages which are equalwhen the loads on the two motor banks M and M, are equal. The taps 112aand 114a are provided for calibration purposes, i.e. so that shouldthere by any difference in the current characteristics of the two motorswhich would tend to result in a difference in voltage between terminals111 and 112 when the loads on the motors are equal, the taps 112a and114a can be adjusted. to assure that the voltage applied to therectifiers 118 and 120 is exactly equal at such times. The proportioningrelay circuit 126 responds to the voltages applied to its inputterminals 122 and 124 to supply current through its output leads 130 and132 to tilt motor M; of a direction and magnitude dependent upon thepolarity of the voltage between input terminals 122 and 124. Theconnections of leads 130 and 132 to the tilt motor M are such that ifthe voltage at input terminal 124 becomes more negative than that atinput terminal 122, indicating that the load on motor bank M is largerthan that on motor bank M the tilt motor M will be operated to tilt thedischarge trough in the direction to deliver less slag to the spinnerheads operated by motor bank M, and more slag to the spinner headsrotated by motor bank M When the delivery of slag to the two sets ofspinner heads is thereby equalized, the loads on the two sets of motorbanks will become equal, there will be no substantial difference involtage at the input terminals 122 and 124, and current from outputleads 130 and 132 to tilt motor M will be terminated, arresting thetilting of the discharge trough. A similar operation will occur for anopposite unbalanced loading of the spinner heads.

The proportioning relay circuit 126 may take any of a large variety ofconventional forms. To avoid continuous angular motion of the dischargetrough and hunting by the servo loop provided by the apparatus of FIG.14, circuit 126 preferably has a relatively slow time constant,andincludes an appropriate thresholding circuit such that the tilt motorM will not be operated until the difference in voltage between inputterminals 122 and 124 become substantial. Preferably, also, the circuit126 is of a nature such that when the input voltage at terminals 122 and124 exceeds said threshold value, the tilt motor M will be operated onlyfor a predetermined time interval less than that which can causeovercorrection of the angle of tilt, after which time interval thecircuit 126 will again sense any remaining difference in the inputvoltage between terminals 122 and 124 and again operate the motor M fora predetermined time, if further correction is required. Circuitry iswell known in the art for providing the above-described functions, andit will be understood that circuit 126 may in fact take any of a largevariety of different forms in different applications so long as itserves to provide an output current for operating the tilt motor M inthe direction to reduce the difference in loading on the two motor banksM and M,,.

In the present instance, the spinner assemblies are mounted in acarriage 130 having wheels which ride on stationary trackways 132 and134 so that the spinner assemblies may be retracted from the opening tothe pickup chamber when desired to provide means for gaining access tothe spinner heads, for example for replacement or repair purposes.Additionally, the carriage 130 may be retracted when shutting down thesystem. In the event the cupola is still discharging molten material,the tilt trough 84 is mounted for pivotal movement relative to thedischarge chute of the cupola and a center discharge trough 136 isprovided between the main feed troughs 93 and 95 which dischargesrearwardly to a suitable accumulation area. To this end, the tilt troughis carried by a bracket 142 pivotally connected to the support brace.The bracket 142 as illustrated is generally rectagular, the opposingsides of which abut angularly disposed bumpers 146 of the brace in thedown or operative position of the tilt trough. The bracket and troughare actuatable to an outer position [shown in broken lines in FIG. 8] bymeans of a piston-cylinder actuator 150, the piston connected to thebracket by means ofa link arm exten sion I52.

Considering now the specific details and arrangement of the pickupchamber and with specific reference to FIGS. 1 and 6, the lower end ofthe air return duct is separated from the pickup chamber by a dividingwall 160 which as illustrated has a plurality of openings 162 thereinfor circulation of some of the return air to the pickup chamber.Additionally, a doughnut-shaped manifold 164 is provided whichcommunicates at opposite ends as at 166 and 168 with the twocompartments of the lower end of the air return chamber. This manifoldas illustrated has center dividing wall 120 which in turn is in fluidcommunication with return air inlet chamber 172 extending for a majorportion about the periphery of the spinner head assembly opening 175 tothe pickup chamber. This air inlet manifold has a discharge opening 174to direct the air around the spinner heads in the manner shown in FIG.6.

Means are also provided for selectively adding new air to the return airat the pickup chamber. To this end, in the present instance a pair ofblowers 180 and 182 are provided which communicate through duct work 184and 186 with a fresh air manifold 190 having a discharge outlet 192closely adjacent the opening 174 and circumscribing the periphery of thespinner head opening in the manner shown in FIG. 4. By this arrangementthe velocity and temperature of the air flowing in the system,particularly in the region of the pickup chamber, may be selectivelycontrolled.

Considering now briefly the operation of the apparatus and systemdescribed above, the spinner head assemblies are simply moved into theoperative position wherein the spinner heads are disposed in the pickupchamber as illustrated in FIG. 6. The cupola is then charged in thecknventional manner. The molten material then discharges continuouslyfrom the cupola discharge spout and engages the tiltable trough, whichis normally in a level position, so that substantially the samequantities of molten material flow to the feed troughs for the twospinner head assemblies. Of course, as the material discharges to thespinner heads, it is fiberized by the action of the spinner heads andthe flow of air through the pickup chamber. During the course ofoperation, if the quantity of molten material discharged to eitherspinner head assembly is not substantially uniform, the imbalance in theload on the spinner head assemblies is sensed and the circuit describedabove effects a tilting movement of the trough to correct the imbalance.It is noted that buildup on either the tilt trough or the feed troughsmay result in the imbalance situation. This is an important feature ofthe present invention, since it has been found that overload of thespinner head assemblies results in a substantially increased shotcontent in the fibers.

As the fibers are formed in the pickup chamber and are conveyed upwardlyin the pickup duct, some of the shot separated from the fibersdischarges downwardly through the shot discharge cute 200 to a screwtype conveyor 202 where it is accumulated at a suitable source. Anotherimportant feature of the present invention is the control of thevelocity and temperature of the circulating medium, in the presentinstance air, through the pickup chamber and in the pickup duct. This iscontrolled in part by the system and specific arrangement of the freshair additive system and the specific configuration and arrangement ofthe return air system including the distribution manifolds providingcommunication between the air chamber and the pickup chamber. Morespecifically, it has been found that when the temperature of thecirculating medium is maintained between 330400 F and the velocity ismaintained at about 2500 feet per minute in the pickup chamber and about4000 feet per minute in the pickup duct 42 and return air duct 44,fibers having a minimum shot content and good strength and resiliencycharacteristics are produced. In order to maintain these conditions, aconventional temperature sensing device 220 may be provided in thepickup duct 42 (see FIGS. 1 and 7) which may be operatively connected toa damper 222 in the duct 52. This provides a means for selectivelycontrolling the amount of air recirculated through the return air duct44 in a balanced system. In other words, as the damper 22 dischargesmore of the circulating air to the atmosphere, fresh air is drawn intothe system through the duct work 184 and 186 and also through thespinner head opening 175. Additionally, the speed of the blower 48 maybe selectively varied to provide forvelocity control of the aircirculated through the pickup chamber.

lclaim:

l. A method for converting molten mineral material into vitreous fiberconsisting of the steps of discharging the molten mineral material to atleast one spinner assembly comprising a plurality of rotating spinnerwheels and disposed in the region of a pickup chamber located at thejuncture of a pickup and return duct of a continuous duct work system,circulating a heated gaseous conveying medium through the duct worksystem, controlling velocity of the gaseous conveying medium in a mannerto quickly convey fibers formed in the pickup chamber on discharge fromthe spinner assembly and effect passage through the pickup duct therebyto produce fibers having a minimum shot content and controllingtemperature of the gaseous conveying medium by recirculating at least aportion thereof thereby producing fibers having good strength andresiliency characteristics.

2. A method as claimed in claim 1 wherein the temperature of theconveying medium is maintained in the range between about 300-400 F.

3. A method as claimed in claim 1 wherein the velocity of the conveyingmedium is in the vicinity of about 2500 feet per minute at the pickupchamber, and about 4000 feet per minute in the duct work system.

4. An apparatus for converting molten mineral material into vitreousfibers comprising a continuous duct work system, means for circulating agaseous conveying medium through the duck work system, said duct worksystem including in series a non-horizontal pickup duct, a separator forseparating fibers from the conveying medium and a conveying mediumreturn duct, a juncture of the pickup duct and return duct defining apickup chamber, at lease one spinner assembly in the region of thepickup chamber, said spinner assembly including a plurality of spinnerwheels operable to effect conversion of the molten mineral material andrandom dispersion of fibers, means for directing the molten mineralmaterial to the wheels of the spinner assembly, means for controllingthe velocity of the gaseous conveying medium in a manner to quicklyconvey fibers formed in the pickup chamber and effect passage throughthe pickup duct thereby to produce fibers having a minimun shot contentand means for controlling temperature of the gaseous conveying medium byrecirculating at least a portion thereof thereby producing fibers havinggood strength and resiliency characteristics.

5. An apparatus as claimed in claim 4 including a manifold systemadjacent the spinner assembly, said manifold means or receiving lowsystem including pressure gaseous conveying medium from the return ductand high pressure gaseous conveying medium and discharge meanscircumscribing the periphery of said spinner assembly.

6. An apparatus as claimed in claim 5 including valve means forselectively controlling the quantity of high pressure gaseous conveyinggnedium introduced to said manifold system. i

7. An apparatus as claimed in claim 4 including temperature sensingmeans in said pickup duct operatively connected to a valve control meansin the return duct for selectively controlling the amount of gaseousconveying medium recirculated through the return duct.

8. An apparatus as claimed in claim 4 including classifying means toreceive and classify fibers discharged from said separator.

9. A system for converting molten mineral material into vitreous fibersincluding a container means for the molten mineral material having atleast one discharge spout, at least one pair of spinner assembliesadjacent said discharge spout, each spinner assembly comprising aplurality of rotatable spinner wheels operable to disperse the moltenmaterial from the cupola to form the fibers, a feed trough for each ofthe spinner assemblies, an inclined distributor trough to receive moltenmaterial from the discharge spout and direct the same to the feedtroughs, control means responsive to load on spinner wheels to actuatesaid inclined distributor trough and maintain the distribution of moltenmineral material discharged to each spinner assembly substantiallyuniform.

10. A system as claimed in claim 9 including motor actuating means foreach of the spinner assemblies, an actuator for the distributor troughand load sensing means for the spinner assembly, said motor actuatormeans operable in response to load variations to effect operation ofsaid distributor trough actuator to vary distribution of molten materialto said spinner assemblies to maintain a substantially uniformdistribution.

1. A method for converting molten mineral material into vitreous fiberconsisting of the steps of discharging the molten mineral material to atleast one spinner assembly comprising a plurality of rotating spinnerwheels and disposed in the region of a pickup chamber located at thejuncture of a pickup and return duct of a continuous duct work system,circulating a heated gaseous conveying medium through the duct worksystem, controlling velocity of the gaseous conveying medium in a mannerto quickly convey fibers formed in the pickup chamber on discharge fromthe spinner assembly and effect passage through the pickup duct therebyto produce fibers having a minimum shot content and controllingtemperature of the gaseous conveying medium by recirculating at least aportion thereof thereby producing fibers having good strength andresiliency characteristics.
 2. A method as claimed in claim 1 whereinthe temperature of the conveying medium is maintained in the rangebetween about 300*-400* F.
 3. A method as claimed in claim 1 wherein thevelocity of the conveying medium is in the vicinity of about 2500 feetper minute At the pickup chamber, and about 4000 feet per minute in theduct work system.
 4. An apparatus for converting molten mineral materialinto vitreous fibers comprising a continuous duct work system, means forcirculating a gaseous conveying medium through the duck work system,said duct work system including in series a non-horizontal pickup duct,a separator for separating fibers from the conveying medium and aconveying medium return duct, a juncture of the pickup duct and returnduct defining a pickup chamber, at lease one spinner assembly in theregion of the pickup chamber, said spinner assembly including aplurality of spinner wheels operable to effect conversion of the moltenmineral material and random dispersion of fibers, means for directingthe molten mineral material to the wheels of the spinner assembly, meansfor controlling the velocity of the gaseous conveying medium in a mannerto quickly convey fibers formed in the pickup chamber and effect passagethrough the pickup duct thereby to produce fibers having a minimun shotcontent and means for controlling temperature of the gaseous conveyingmedium by recirculating at least a portion thereof thereby producingfibers having good strength and resiliency characteristics.
 5. Anapparatus as claimed in claim 4 including a manifold system adjacent thespinner assembly, said manifold system including means for receiving lowpressure gaseous conveying medium from the return duct and high pressuregaseous conveying medium and discharge means circumscribing theperiphery of said spinner assembly.
 6. An apparatus as claimed in claim5 including valve means for selectively controlling the quantity of highpressure gaseous conveying medium introduced to said manifold system. 7.An apparatus as claimed in claim 4 including temperature sensing meansin said pickup duct operatively connected to a valve control means inthe return duct for selectively controlling the amount of gaseousconveying medium recirculated through the return duct.
 8. An apparatusas claimed in claim 4 including classifying means to receive andclassify fibers discharged from said separator.
 9. A system forconverting molten mineral material into vitreous fibers including acontainer means for the molten mineral material having at least onedischarge spout, at least one pair of spinner assemblies adjacent saiddischarge spout, each spinner assembly comprising a plurality ofrotatable spinner wheels operable to disperse the molten material fromthe cupola to form the fibers, a feed trough for each of the spinnerassemblies, an inclined distributor trough to receive molten materialfrom the discharge spout and direct the same to the feed troughs,control means responsive to load on spinner wheels to actuate saidinclined distributor trough and maintain the distribution of moltenmineral material discharged to each spinner assembly substantiallyuniform.
 10. A system as claimed in claim 9 including motor actuatingmeans for each of the spinner assemblies, an actuator for thedistributor trough and load sensing means for the spinner assembly, saidmotor actuator means operable in response to load variations to effectoperation of said distributor trough actuator to vary distribution ofmolten material to said spinner assemblies to maintain a substantiallyuniform distribution.